1. Field of the Invention
The present invention relates to a surgical device for stapling and fastening body tissues, more specifically the severed edges of tubular organs such as the large intestine or the small intestine.
2. Description of the Related Art
Tissue stapling/fastening devices are known which are designed to stitch together the severed edges of two normal portions of a tubular organ such as the large intestine, the small intestine or the duodenum, after a diseased portion of the organ has been excised. A device of this type makes it easy for a surgeon to apply staples or a suture ring, stitching together the normal portions of the organ. Thus, the device helps to shorten the time required for a surgical operation.
The tissue stapling/fastening device has an insertion section comprising a shaft which can be inserted into a tubular organ such as the large intestine. The distal end portion of the insertion section can hold staples or a suture ring. The insertion section is rigid, either straight or curving.
The rigid insertion section can hardly be inserted into a curving tubular organ such as the large intestine or the small intestine. If it is inserted into the tubular organ, it cannot reach the deepest portion of the organ. To stitch a deep portion of the organ, the organ is incised at a portion near the target portion of the organ, and the insertion section is inserted through the incision into the target portion. This is a complex operation.
New types of tissue stapling/fastening devices have been developed. Published Unexamined Japanese Patent Application No. 63-305854 discloses a device in which a flexible shaft connects the operation section and the stapling section. The operation section has a means for maintaining the shaft in a bent state. Published Unexamined Japanese Patent Application No. 59-501777 (WO 84/01095) discloses a similar device, in which hydraulic power is applied from the operation section to the stapling section to deform staples and excise unnecessary tissues.
To stitch together the severed edges of the portions of a tubular organ located near the anus, such as the rectum or the sigmoid colon, the insertion section of the device may be inserted through the anus. It is difficult, however, to guide the distal end of the insertion section to any position deeper than rectum or the sigmoid colon. To excise the diseased portion of the large intestine by using a laparoscope, without forming an incision in the abdominal wall, it would be impossible to insert the insertion section of a tissue stapling/fastening device.
In the device disclosed in Published Unexamined Japanese Patent Application No. 63-305854, the shaft is bent due to the resistance of the inner surface of the organ as it is inserted into the cavity in that organ, in order to excise the organ. Therefore, the shaft can hardly be bent in the same way as does the curving portion of the organ, and cannot smoothly pass therethrough. Consequently, it would be difficult to insert the shaft into the organ.
In the device disclosed in Published Unexamined Japanese Patent Application No. 59-501777, the shaft must be bent in accordance with the resistance of the inner surface of the organ until the stapling section reaches the tissues in the organ. The shaft must be rigid enough to transmit a force for stitching the tissues and a force for excising unnecessary parts of the tissues within an organ. Because of its rigidity, however, the shaft can hardly be bent or deformed complementary to the curving inner surface of the organ.
With either tissue stapling/fastening device, to insert the stapling section into the organ to reach the target tissues existing therein, it is necessary to incise that part of the organ wall which is near the target tissues, thereby forming an opening large enough to allow the passage of the stapling section into the organ. The opening must of course be stitched and closed after the completion of the intra-organ surgical treatment. Thus, to incise the wall of the organ for the purpose of inserting the stapling section into the organ is undesirable in view of the pain and discomfort the patient will inevitably suffer.
When the severed edges c of two parts of an intestine a (e.g., the large intestine) are stitched together with staples b, as shown in FIG. 61, by means of the conventional tissue stapling/fastening device, the edges c are located inside the intestine a. From the outer appearance of the intestine a, it is impossible to determine whether or not the parts of the intestine a have been stitched steadfastly.